package com.zhang.common.util.io;

import com.alibaba.druid.util.Base64;

import javax.xml.bind.DatatypeConverter;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class IoUtils {

    /**
     * 将inputstream转为Base64
     *
     * @param is
     * @return
     * @throws Exception
     */
    public static String getBase64FromInputStream(InputStream is) throws Exception {
        // 将图片文件转化为字节数组字符串，并对其进行Base64编码处理
        byte[] data = null;

        // 读取图片字节数组
        try {
            ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
            byte[] buff = new byte[100];
            int rc = 0;
            while ((rc = is.read(buff, 0, 100)) > 0) {
                swapStream.write(buff, 0, rc);
            }
            data = swapStream.toByteArray();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    throw new Exception("输入流关闭异常");
                }
            }
        }
        return DatatypeConverter.printBase64Binary(data);
    }

}
